Panthers owner David Tepper kept that option open when he met with reporters on Tuesday for a media roundtable. Reporters asked Tepper about the Panthers quarterback's future availability due to lingering shoulder issues.
Luck returned this season to led the Colts to the AFC divisional round.
"Now, we would have to do other things and we'd have to go out and get another quarterback, which, if you could find me some more cap space, I'd appreciate that."
Newton, 29, completed a career-best 67.9 percent of his passes last season for 3,395 yards, 24 touchdowns and 13 interceptions in 14 start in 2018. He also ran for 488 yards and four scores this season.
The three-time Pro Bowl selection and 2015 NFL MVP was shut down for the Panthers' final two games of the season as he dealt with the shoulder pain. Newton had shoulder surgery in 2017. Tepper said he did not know if Newton will require another shoulder surgery.
Tepper said the Panthers may need to create some cap space to prepare for the possibility that Newton's shoulder is not in a good place before the 2019 season. Carolina has about $25 million in cap space.
Tepper's $2.275 billion purchase of the Panthers was made official in July. Newton, 29, is signed through 2020. Taylor Heinicke and Kyle Allen are the Panthers' backup quarterbacks.